Electronic faucets for long-term operation

ABSTRACT

An electronic faucet ( 10 ) mounted on a countertop ( 12 ) includes a housing, at least one fluid inlet line ( 24   a   , 24   b ) extending into the housing, a fluid outlet ( 46 ) from the housing, a solenoid ( 142, 143 ) for operating a valve controlling the fluid flow between at least one inlet line and the outlet, and a control circuit ( 206 ) for controlling the opening and closing of the valve.

[0001] This application is a continuation of PCT ApplicationPCT/US02/38757, filed on Dec. 4, 2002, entitled “Electronic Faucets forLong-Term Operation,” which is a continuation-in-part of U.S.application Ser. No. 10/011,423 filed on Dec. 4, 2001. The PCTApplication PCT/US02/38757 also claims priority from U.S. Prov.Application 60/391,282 filed Jun. 24, 2002.

[0002] This invention relates to electronic metering faucets and methodsfor operating and controlling such faucets.

BACKGROUND OF THE INVENTION

[0003] In public facilities or large private facilities, there areseveral different types of metering faucets in use today. Many aremanually activated to turn on the water by pressing the faucet head andare hydraulically timed so that the water remains on for a set period oftime after depression of the head. Some of these faucets have separatehead allowing separate control over the hot and cold water. Othermetering faucets mix the incoming hot and cold water streams and, whenactuated, deliver a tempered output stream.

[0004] Also known is a manually activated metering faucet whose on-timeis controlled electronically. Still other known faucets are activatedelectronically when the user positions a hand under the faucet.automatic water dispensing systems have provided numerous advantagesincluding improved sanitation, water conservation, and reducedmaintenance cost. Since numerous infectious diseases are transmitted bycontact, public-health authorities have encouraged the public andmandated to food workers the exercise of proper hygiene includingwashing hands effectively. Effective hand washing has been made easierby automatic faucets. Automatic faucets typically include an objectsensor that detects presence of an object, and an automatic valve thatturns water on and off based on a signal from the sensor. If the watertemperature in an automatic faucet is not in an optimal range,individuals tend to shorten their hand washing time. To obtain anoptimal water temperature, a proper mixing ratio of hot and cold waterand proper water actuation has to be achieved. Automatic faucets usuallyuse a preset valve that controls water flow after mixing.

[0005] The hydraulically timed faucets are disadvantaged in that it isdifficult to accurately control the on-time of the faucet over the longterm because of mains pressure changes and foreign matter build up inthe faucet which can adversely affect the hydraulic controls within thefaucet. On the other hand, the known electronic faucets can not alwaysdiscriminate between a user's hand and other substances and objectswhich may be brought into proximity to the faucet, e.g. a reflectiveobject disposed opposite the faucet's infrared transceiver, soap buildup on the-faucet's proximity sensor, etc. Resultantly, those priorfaucets may be turned on inadvertently and/or remain on for too long atime resulting in wastage of water.

SUMMARY OF THE INVENTION

[0006] The present invention generally relates to automatic sensor basedfaucets and methods of operating such faucets.

[0007] According to another aspect, the present invention is asensor-based flow-control system, such as a sensor-based faucet. Thesensor-based flow-control system includes a valve interposed in aconduit and controlled by an electromechanical actuator, and a sensorfor generating sensor output signals to an electronic control circuitconstructed and arranged to provide the control signals to theelectromechanical actuator for opening and closing the valve.

[0008] Specifically, the present invention is a sensor-based faucethaving a hot and cold water inlet and an outlet. A sensor generatessensor output signals provided to an electronic control circuitconstructed and arranged to provide control signals to anelectromechanical actuator.

[0009] Preferred embodiments of this aspect include one or more of thefollowing features:

[0010] The electromechanical actuator may be coupled to only one valveinterposed in one conduit delivering premixed hot and cold water. Theelectromechanical actuator may coupled to another type of a valve forcontrolling flow of hot and cold water in two separate conduits, asdescribed in PCT application PCT/US01/43277. Alternatively, the controlsignals may be delivered to two electromechanical actuators constructedand arranged to control separately two valves and thereby controlseparately water flow in two separate conduits with hot and cold waterdelivered to a faucet.

[0011] According to another aspect of the present invention, a faucet isactivated by touch and/or proximity to the faucet and thereafterprovides a consistent water delivery period over the life of the faucet.

[0012] The described electronic metering faucets have numerousadvantages. The electronic faucets provide long-term reliable operation.The faucets are activated using an object sensor or a touch sensor(capacitive or other touch or proximity)

[0013] The faucet is electronically timed and maintains its timingaccuracy over the life of the faucet.

[0014] The described faucets are self-contained battery operated,electronic metering faucets which can operate for over two, three ormore years between battery replacements. The faucet which has a minimumnumber of moving parts, and the individual parts may be accessed quiteeasily for maintenance purposes. The faucets can be manufactured andmaintained at relatively low cost.

[0015] According to another aspect, the present invention is a novelinterface for calibrating or programming a sensor-based faucet. Theinterface interacts with a user via an object sensor couple to amicroprocessor for controlling the water flow in the faucet. Thesensor-based faucet includes a valve interposed in a conduit andcontrolled by an electromechanical actuator, and a sensor for generatingsensor output signals to an electronic control circuit constructed andarranged to provide the control signals for opening and closing thevalve. The control circuit may direct the valve to provide apredetermined number of water bursts at different steps of variousalgorithms to communicate with a user. The control circuit may controlthe valve to provide pulsating water delivery when sensing differentproblems such as a battery low state, an electrical problem or amechanical problem in one of the faucet's elements.

[0016] According to another aspect, the present invention is asensor-based faucet that is constructed using materials that prevent orsignificantly reduce bacterial or other biological growth in waterregulated by the faucet. Furthermore, sensor-based faucet that isconstructed to execute automatically a flushing algorithm in order toflush water contained in the faucet for a predetermined period of timeand thus flush bacterial contamination that may have grown inside thefaucet. The control circuit may provide also signals to an optical,acoustic or other indicator when such flushing algorithm is executed.

[0017] According to another aspect, the present invention is asensor-based faucet having a hot and cold-water inlet and an outlet. Asensor generates sensor output signals provided to an electronic controlcircuit constructed and arranged to provide control signals to anelectromechanical actuator. The control circuit provides also signal toan optical, acoustic or other indicator starts signaling when theactuator first opens the valve. The control circuit provides signals tothe indicator that continues signaling for a predetermined duration toindicate to a user that a time interval prescribed as necessary foreffective hand washing has not yet expired. When the interval doesexpire, the user is thereby assured that he has complied with therelevant duration regulation.

[0018] According to another aspect, the present invention is a novelvalve device and the corresponding method for controlling flow-rate offluid between the input and output ports of the valve device. A novelvalve device includes a fluid input port and a fluid output port, avalve body, and a fram assembly. The valve body defines a valve cavityand includes a valve closure surface. The fram assembly provides twopressure zones and is movable within the valve cavity with respect aguiding member. The fram assembly is constructed to move to an openposition enabling fluid flow from the fluid input port to the fluidoutput port upon reduction of pressure in a first of the two pressurezones and is constructed to move to a closed position, upon increase ofpressure in the first pressure zone, creating a seal at the valveclosure surface.

[0019] According to preferred embodiments, the two pressure zones areformed by two chambers separated by the fram assembly, wherein the firstpressure zone includes a pilot chamber. The guiding member may be a pinor internal walls of the valve body.

[0020] The fram member (assembly) may include a pliable member and astiff member, wherein the pliable member is constructed to come incontact with a valve closure surface to form seal (e.g., at a sealinglip located at the valve closure surface) in the closed position. Thevalve device may include a bias member. The bias member is constructedand arranged to assist movement of the fram member from the openposition to the closed position. The bias member may be a spring.

[0021] The valve is controlled, for example, by an electromechanicaloperator constructed and arranged to release pressure in the pilotchamber and thereby initiate movement of the fram assembly from theclosed position to the open position. The operator may include alatching actuator (as described in U.S. Pat. No. 6,293,516, which isincorporated by reference), a non-latching actuator (as described inU.S. Pat. No. 6,305,662, which is incorporated by reference), or anisolated operator (as described in PCT Application PCT/US01/51098, whichis incorporated by reference). The valve may also be controlled may alsoincluding a manual operator constructed and arranged to release pressurein the pilot chamber and thereby initiate movement of the fram memberfrom the closed position to the open position.

[0022] The novel valve device including the fram assembly may be used toregulate water flow in an automatic or manual faucet.

[0023] According to yet another aspect, the present invention is a novelelectromagnetic actuator and a method of operating or controlling suchactuator. The electromagnetic actuator includes a solenoid wound aroundan armature housing constructed and arranged to receive an armatureincluding a plunger partially enclosed by a membrane. The armatureprovides a fluid passage for displacement of armature fluid between adistal part and a proximal part of the armature thereby enablingenergetically efficient movement of the armature between open and closedpositions. The membrane is secured with respect to the armature housingand is arranged to seal armature fluid within an armature pocket havinga fixed volume, wherein the displacement of the plunger (i.e., distalpart or the armature) displaces the membrane with respect to a valvepassage thereby opening or closing the passage. This enables low energybattery operation for a long time.

[0024] Preferred embodiments of this aspect include one or more of thefollowing features: The actuator may be a latching actuator (including apermanent magnet for holding the armature) of a non-latching actuator.The distal part of the armature is cooperatively arranged with differenttypes of diaphragm membranes designed to act against a valve seat whenthe armature is disposed in its extended armature position. Theelectromagnetic actuator is connected to a control circuit constructedto apply said coil drive to said coil in response to an output from anoptional armature sensor.

[0025] The armature sensor can sense the armature reaching an endposition (open or closed position). The control circuit can directapplication of a coil drive signal to the coil in a first drivedirection, and in responsive to an output from the sensor meeting apredetermined first current-termination criterion to start or stopapplying coil drive to the coil in the first drive direction. Thecontrol circuit can direct or stop application of a coil drive signal tothe coil responsive to an output from the sensor meeting a predeterminedcriterion.

[0026] According to yet another aspect, the present invention is a novelassembly of an electromagnetic actuator and a piloting button. Thepiloting button has an important novel function for achieving consistentlong-term piloting of a main valve. The present invention is also anovel method for assembling a pilot-valve-operated automatic flowcontroller that achieves a consistent long-term performance.

[0027] Method of assembling a pilot-valve-operated automatic flowcontroller includes providing a main valve assembly and a pilot-valveassembly including a stationary actuator and a pilot body member thatincludes a pilot-valve inlet, a pilot-valve seat, and a pilot-valveoutlet. The method includes securing the pilot-valve assembly to themain valve assembly in a way that fluid flowing from a pressure-reliefoutlet of the main valve must flow through the pilot-valve inlet, pastthe pilot-valve seat, and through the pilot-valve outlet, whereby thepilot-valve assembly is positioned to control relief of the pressure inthe pressure chamber (i.e., pilot chamber) of the main valve assembly.The main valve assembly includes a main valve body with a main-valveinlet, a main-valve seat, a main-valve outlet, a pressure chamber (i.e.,a pilot chamber), and a pressure-relief outlet through which thepressure in the pressure chamber (pilot chamber) can be relieved. A mainvalve member (e.g., a diaphragm, a piston, or a fram member) ismovable,between a closed position, in which it seals against themain-valve seat thereby preventing flow from the main inlet to the mainoutlet, and an open position, in which it permits such flow. During theoperation, the main valve member is exposed to the pressure in thepressure chamber (i.e., the pilot chamber) so that the pressurized pilotchamber urges the main valve member to its closed position, and theunpressurized pilot chamber (when the pressure is relieved using thepilot valve assembly) permits the main valve member to assume its openposition.

[0028] Briefly, one type of the metering faucet is a touch activated,electronically timed faucet that can deliver water at a selectedtemperature for a preset water delivery period which, unless reset,remains substantially constant, i.e. within 2%, over the faucet's lifespan. The faucet includes a simple non-water-contacting housing orencasement, which is adapted to be secured to a sink or countertop.Supported in the housing is a single cartridge containing most of thehydraulic components of the faucet including a solenoid-actuated valvewhich controls the delivery of water from hot and cold water lines-to asingle outlet at the end of a faucet spout formed by the housing. Thehousing or encasement also supports a stationary faucet head whichcontains all of the electrical components necessary to actuate the valvefor a selected period of time after a user's hand touches or is movedinto close proximity to a selected target area on the head.

[0029] As we shall see, the faucet includes provisions for preventinginadvertent faucet activation by non-environmental factors such as soapbuild up, contact by paper towels, etc., as well as accidental humancontact. This is accomplished by dynamically adjusting in real time thefaucet's activation sensitivity depending upon the prevailingconditions. Once activated, the faucet will deliver a stream of water ata set temperature for a predetermined time period. At the end of thatperiod, the faucet's internal controls will issue a shut-off command,which positively shuts off the faucet's solenoid valve.

[0030] Further as we will come apparent, the faucet is designed so thatits components can readily be made and assembled and is accessed quieteasily by maintenance personnel for repair purposes. Still, the faucetcan be made in quantity at a relatively low cost.

BRIEF DESCRIPTION OF THE DRAWINGS

[0031]FIG. 1 is a front elevational view with parts in section showing afaucet installed on a countertop.

[0032]FIG. 2 is a sectional view of one embodiment of the faucet takenalong line 2-2 of FIG. 1.

[0033]FIG. 2A is a sectional view of another embodiment of the faucettaken along line 2-2 of FIG. 1.

[0034]FIG. 2B is a sectional view taken along the line of 2B-2B of FIG.2.

[0035]FIG. 3 is a fragmentary sectional view showing a portion of theFIG. 2 faucet in greater detail.

[0036]FIG. 4 is a fragmentary sectional view of a portion of the faucetshown in FIG. 2.

[0037]FIG. 4A is a fragmentary sectional view of a portion of the faucetshown in FIG. 2A.

[0038]FIG. 5 is an enlarged sectional view of a valve for controllingfluid flow in the faucet shown in FIGS. 2A and 4A.

[0039]FIG. 5A is a perspective exploded view of the valve shown in FIG.5.

[0040]FIG. 5B is an enlarged sectional view of another embodiment of thevalve shown in FIG. 5.

[0041]FIG. 5C is an enlarged sectional view of another embodiment of thevalve shown in FIG. 5.

[0042]FIG. 6 is another embodiment of a faucet using a valve devicelocated below a faucet mounting surface.

[0043]FIG. 6A is an enlarged sectional view of the valve device shown inFIG. 6.

[0044]FIG. 6B is a perspective exploded view of the valve device shownin FIG. 6A.

[0045]FIG. 7 is a sectional view of a first embodiment of anelectromechanical actuator for controlling any one of the valves shownin FIGS. 5 through 6B.

[0046]FIG. 7A is a perspective exploded view of the electromechanicalactuator shown in FIG. 7

[0047]FIG. 7B is a sectional view of a second embodiment of anelectromechanical actuator for controlling the valves shown in FIGS. 5through 6B.

[0048]FIG. 7C is a sectional view of a third embodiment of anelectromechanical actuator for controlling the valves shown in FIGS. 5through 6B.

[0049]FIG. 7D is a sectional view of another embodiment of a membraneused in the actuator shown in FIGS. 7 through 7C

[0050]FIG. 7E is a sectional view of another embodiment of the membraneand a piloting button used in the actuator shown in FIGS. 7 through 7C.

[0051]FIG. 7F is a sectional view of another embodiment of an armaturebobbin used in the actuator shown in FIGS. 7 through 7C.

[0052]FIG. 8 is a block diagram showing a control circuitry forcontrolling operation of the faucet shown in FIG. 1 or FIG. 6

[0053]FIG. 8A is a flow chart of an algorithm performed by amicrocontroller used in the control circuitry.

[0054]FIG. 9 is a block diagram of another embodiment of controlcircuitry for controlling operation of the faucet shown in FIG. 1 orFIG. 6

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0055] Referring to FIG. 1, the subject faucet 10 is shown mounted to acountertop 12. The faucet includes a housing or encasement 14 having amore or less semicircular flange 14 a at its lower end. Fasteners 16inserted through holes 18 in countertop 12 are threaded into holes 22 inflange 14 a to secure the faucet to the countertop. Faucet 10 alsoincludes flexible hot and cold water lines 24 a and 24 b which extendfrom the lower end of housing 14 through a large opening 26 incountertop 12. These water lines are adapted to be coupled to hot andcold water mains.

[0056] As shown in FIGS. 1 and 2, faucet housing 14 actually consists ofa shell-like part 32 forms an upright main body portion 32 a (includingflanges 14 a) and the upper portion 32 b of a spout extending out fromthe main body portion 32 a. The open front of main body portion 32 a andthe underside of the spout portion 32 b are normally closed by aremovable cover plate 36 clipped or otherwise secured to the edges ofportions 34 a and 34 b.

[0057] Faucet 10 also has a stationary head 38 mounted to the top ofhousing 14. Head 38 incorporates a touch sensor shown generally at 42which, when touched, activates faucet 10 so that a stream of temperedwater issues from an outlet 44 centered in an opening 46 provided in thecover plate 36 near the end of spout 34.

[0058] As best seen in FIG. 2, the upper end segment of the main bodyportion 32 a has a thickened internally threaded wall forming a circularledge 46 which functions as a stop for a cylindrical cartridge showngenerally at 48. Cartridge 48 includes a side wall 52 a, a bottom wall52 b, the top of the cartridge being open. A circular flange 54 extendsout from side wall 52 a and that flange is adapted to seat against ledge46. The cartridge is held in place within the shell portion 32 a by abushing 56 which is screwed down into the open top of main body portion32 a.

[0059] An opening 58 is provided in the side wall 52 a of cartridge 48and an exterior collar 62 surrounds that opening into which is press fitone end of a conduit 64 which extends within the upper spout portion 32b. The other end of that conduit constitutes the faucet outlet 44.Preferably, there is sufficient clearance between the outlet 44 and theedge of opening 46 in the cover plate 36 to permit a conventionalaerator (not shown) to be installed at outlet 44.

[0060] Referring to FIGS. 2 and 3, cartridge 48 includes a pair of sideby side inlet conduits 72 a and 72 b which extend down from thecartridge bottom wall 52 b. Formed midway along each such conduit is anannular valve seat 74 for seating vertically moveable valve member 76.Each valve member is biased against its seat by a coil spring 78 seatedwithin a sleeve 82 extending up from a cartridge bottom wall 52 b withinthe cartridge. Each spring 78 is compressed between the upper end of thecorresponding valve member 76 and a stop 82 a provided at the upper endof each sleeve 82.

[0061] The lower end segment of the cartridge conduit 72 a forms afemale connector 84 which is arranged to receive a corresponding maleconnector 86 provided at the upper end of the water line 24 a. Theillustrated connector 86 is a conventional quick release connector whichis held in place by a C-clip 88 whose arms extend through slots 92 inthe opposite sides of connector 84 and engage in a groove 86 a in maleconnector 86.

[0062] The cold water line 24 b is connected in a similar fashion toconduit 72 b of cartridge 48. It is thus apparent from FIG. 3 that eachof the hot and cold water lines 24 a, 24 b conducts water into cartridge48 via a check valve so that water can flow into, but not out of,cartridge 48 via conduits 72 a and 72 b.

[0063] The cartridge 48 contains an electromechanical valve assemblyshown generally at 96 which controls the flow of hot and cold water fromlines 24 a and 24 b to the faucet outlet 44. As shown in FIGS. 2 to 4,assembly 96 sits on the two sleeves 82 projecting up from the cartridgebottom wall 52 b. As specified in FIG. 4, the valve assembly 96comprises lower filter housing shown generally at 98, an upper valvehousing in 102, the two housings being releasably connected together bycoupling 104. The housing 98 is shaped generally like an inverted cup.It has a sidewall 106 and a top wall 106 b. The open bottom of thehousing is substantially closed by a circular metering plate 108, whichis the part of the valve assembly that actually sits on the sleeves 82extending up from the cartridge bottom wall 52 a. Referring also to FIG.4, the metering plate 108 does have metering holes 110 which are alignedwith sleeves 82 so that hot and cold water is conducted via those holesfrom the water lines 24 a and 24 b to the interior of housing 98.Housing 98 contains a vertically oriented filter element 112 whoseopposite ends are captured by an upstanding wall 114 formed in plate 108and a second wall 116 which extend down from the housing top wall 106 b.There is also an opening 118, near the housing top wall 106 b, whichprovides water passage with the interior of the tubular neck 122extending up around the housing top wall 106 b.

[0064] The interior of housing 98 is configured so that hot and coldwater entering the housing is conducted to the periphery of the filterelement 112 whereupon the water flows into the interior of the filterelement and out of the filter element through the large opening 118 andneck 122. The flow rates of the hot and cold water into the housing arecontrolled by the relative sizes of the metering holes 110 and themetering plate 108. The hot and cold water are mixed within housing 98so that the water leaving the housing through the neck 122 has aselected temperature. That temperature may be changed by substitutingdifferent metering plates 108 in the valve assembly. Alternatively, arotatably adjustable metering plate with holes co-operatively arrangedwith metering holes 110 is used to adjust the mixing ratio of hot andcold water.

[0065] Shown in FIG. 4, the upper end of neck 122 is shaped leftwardlyextending circular valve seat 124. When housing 98 is connected tohousing 102 by coupling 104, a valve member 126 in the form of adiaphragm is adapted to move up and down with respect to valve seat 124to control the flow of water out of the neck 122. A valve member 126 issupported on its periphery within the valve housing 102.

[0066] Still referring to FIG. 4, the upper valve housing 102 has acylindrical side wall 102 a and a relatively thick bottom wall 102 b thetop of the housing being open. A flange 102 c encircles sidewall 102 aabout a third of the way down on that wall. Also an upper end segment ofthe sidewall is threaded as shown at 106.

[0067] Housing 102 is arranged to contain a cylinder solenoid 142 havingan externally threaded neck 142 a which is threaded into a collar 113which extends up from the housing bottom wall 102 b. Solenoid 142 has anarmature plunger 40 which extends down through the housing bottom wall102 b and is connected to diaphragm member 126 which is part of a moreor less conventional pilot valve assembly, e.g. of the type described inU.S. Pat. No. 5,125,621, the contents of which is hereby incorporatedherein by reference. When solenoid 142 is energized, its armature 140 isretracted thereby opening a vent passage 136 b. Vent passage 136 b thenis in communication with a pilot chamber 132 via a vent passage 136 a.Releasing pressure in pilot chamber 132 moves diaphragm valve member 126away from valve seat 124 allowing water to flow from the filter housing98 past the valve seat to the opening 58 (FIG. 3) in cartridge 48 andthence via conduit 64 to the faucet outlet 44 shown in FIG. 2.

[0068] On the other hand, when solenoid plunger 140 seals passage 136 b,pressure in pilot chamber 132 increases by water flowing through aV-shaped or U-shaped groove in the pin and opening 146. When thepressure is equalized, diaphragm member 126 is seated against valve seat124, and no water flows from the faucet.

[0069] As shown in FIG. 2, the valve assembly 96 is positioned incartridge 48 so that the meter in plate 108 sits on the sleeves 82 withthe metering holes 110 in that plate is aligned with those sleeves. Inthis position of the cartridge, the flange 102 c of the valve housing102 sits on the upper edge of the cartridge. To retain the valveassembly in this position, an externally threaded bushing is screweddown into the upper end segment of the main body portion 32 a of housing32. The bushing has a radially inwardly extending flange which bearsdown against the flange 104 of the valve housing 102 to hold the valveassembly in place within the cartridge 48. As shown in FIG. 2, whenseated, the upper end of the bushing is flush with the upper end of thehousing main body portion 32 a and the threaded upper end 106 of thevalve housing 102 extends appreciably above the bushing.

[0070] Referring now to FIGS. 2 and 2A, the faucet head or cap 38 issecured to the upper end of the valve housing 32. Head 38 comprises alower housing portion 184 comprising a bottom wall 184 a and a sidewall184 b which flares out and up above the faucet spout 34. A large hole186 is provided in bottom wall 184 a so that the housing portion 184 canbe seated on the top of the main body portion 32 a and the bushing. Acollar surrounds opening 186, which extends down between the sidewall102 a of valve housing 102 and the bushing with the bottom of thatcollar resting on the flange 184 a to help stabilize head 38. Thehousing portion 184 b is held in place by an internally threaded ring192 which is turned down onto the threaded upper end 106 of the valveassembly housing 102 a.

[0071] Referring to FIG. 2B, faucet head 38 also includes an upperhousing portion 194 in the form of a cap. Portion 194 includes a topwall 194 a and an all-around side wall 194 b whose lower edge interfitswith the upper edge of housing portion 184 so that the head forms ahollow enclosure. Housing portion 194 is releasably secured to housingportion 184 by a set screw 196 which is screwed into a threaded hole 198in the housing portion side wall 194 b at the rear of the faucet. Whentightened, the set screw 196 engages a detent 202 formed at the rear ofthe housing portion 184 as also shown in FIG. 2.

[0072] As noted above, the faucet head 38 contains the electricalcomponents necessary to operate the faucet's valve assembly 96. Moreparticularly, as shown in FIGS. 2 and 2B, a printed circuit board 206 issecured by threaded fasteners 208 to a pair of posts 210 extending downfrom the top wall 194 a of the upper housing section 194. Secured to theunderside of the printed circuit board 206 is a battery holder 212 whichsupports a plurality of batteries B and electrically connects thosebatteries to terminals on the printed circuit board 206 so as to powerthe various electrical components on the printed circuit board to bedescribed later. The batteries B may be releasably secured to thebattery holder 212 by a strap 214 or other suitable means.

[0073] As best seen in FIG. 2, an electrically lead 216 extends up fromcircuit board 206 to a metal pad 218 incorporated into a top wall 194 aof the upper housing section 194. Pad 218 is surrounded by anelectrically insulating ring 222 which electrically isolates the padfrom the remainder of top wall 194 a. That pad 218 constitutes thefaucet's touch sensor 42 also described in connection with thecircuit/block diagram below. As described in connection with FIG. 2, allof the electrical components in head 38 may be accessed simply byloosening the set screw 196 and separating the upper housing 194 fromsection 184.

[0074]FIG. 5 illustrates a preferred embodiment of a valve 500 used inthe faucet embodiment shown in FIGS. 2A and 4A, and in the faucetembodiment shown in FIGS. 6, 6A and 6B. In general, valve device 10includes an input port and an output port both in communication with afram member constructed and arranged to open or close fluid flow betweenthe two fluid ports. The design of the fram member enables a relativelyhigh flow rate between the input port and the output port, when comparedto a prior art diaphragm valves of similar dimensions.

[0075] The operation of the fram member is controlled by an actuatorthat may include an electromagnetic solenoid. Valve 10 may also includea manual actuator constructed to control the operation of the frammember independently of the electromagnetic solenoid. The manualactuator may be connected to a separate manual port or to the same portas the solenoid. For example, the manual actuator may be used to controlthe operation of the fram member when loss of electrical power or otherfailure disables the automatic actuator.

[0076] Valve device 500 includes a valve body 513 providing a cavity fora valve assembly 514, an input port 518, and an output port 520. Valveassembly 514 includes a proximal body 522, a distal body 524, and a frammember 526 (FIG. 5A). Fram member 526 includes a pliable member 528 anda support member 532. Pliable member 528 may be a diaphragm-like memberwith a sliding seal 530. Support member 532 may be plunger-like memberor a piston like member, but having a different structural andfunctional properties that a conventional plunger or piston. Valveassembly 514 also includes a guiding member such as a guide pin 536 orsliding surfaces, and includes a spring 540.

[0077] Proximal body 522 includes threaded surface 522A cooperativelysized with threaded surface 524A of distal body 524. Fram member 526(and thus pliable member 528 and a plunger-like member 532) include anopening 527 constructed and arranged to accommodate guiding pin 536.Fram member 526 defines a pilot chamber 542 arranged in fluidcommunication with actuator cavity 550 via control passages 544A and544B. Actuator cavity 550 is in fluid communication with output port 520via a control passage 546. Guide pin 536 includes a V-shaped or U-shapedgroove 538 shaped. and arranged together with fram opening 527 (FIG. 5A)to provide a pressure communication passage between input chamber 519and pilot chamber 550.

[0078] Referring still to FIG. 5, distal body 524 includes an annularlip seal 525 arranged, together with pliable member 528, to provide aseal between input port chamber 529 and output port chamber 521. Distalbody 524 also includes one or several flow channels 517 providingcommunication (in open state) between input chamber 519 and outputchamber 521. Pliable member 528 also includes sealing members 529A and529B arranged to provide a sliding seal, with respect to valve body 522,between pilot chamber 42 and output chamber 521. There are variouspossible embodiments of seals 529A and 529B (FIG. 5). This seal may beone-sided as seal 530 (shown in FIG. 5A) or two-sided seal 529 a and 529b shown in FIG. 5. Furthermore, there are various additional embodimentsof the sliding seal including O-ring etc.

[0079] The present invention envisions valve device 10 having varioussizes. For example, the “full” size embodiment, shown in FIG. 2, has thepin diameter A=0.070″, the spring diameter B=0.360″, the pliable memberdiameter C=0.730″, the overall fram and seal's diameter D=0.812″, thepin length E=0.450″, the body height F=0.380″, the pilot chamber heightG=0.280″, the fram member size H=0.160″, and the fram excursionI=0.100″. The overall height of the valve is about 1.39″ and diameter isabout 1.178″.

[0080] The “half size” embodiment (of the valve shown in FIG. 2) has thefollowing dimensions provided with the same reference letters (each alsoincluding a subscript 1) shown in FIG. 2. In the “half size” valveA₁=0.070″, B₁=0.30, C₁=0.560″, D₁=0.650″, E₁=0.38″, F₁=0.310″,G₁=0.215″, H₁=0.125″, and I₁=0.60″. The overall length of the ½embodiment is about 1.350″ and the diameter is about 0.855″. Similarly,the valve devices of FIG. 5B or 5C may have various larger or smallersizes.

[0081] Referring to FIGS. 5 and 5B, valve 500 receives fluid at inputport 518, which exerts pressure onto diaphragm-like members 528providing a seal together with a lip member 525 in a closed state.Groove passage 538 provides pressure communication with pilot chamber542, which is in communication with actuator cavity 550 viacommunication passages 544A and 544B. An actuator (shown in FIGS. 4A.5C) provides a seal at surface 548 thereby sealing passages 544A and544B and thus pilot chamber 542. When the plunger of actuator 142 or 143moves away from surface 548, fluid flows via passages 544A and 544B tocontrol passage 546 and to output port 520. This causes pressurereduction in pilot chamber 542. Therefore, diaphragm-like member 528 andpiston-like member 532 move linearly within cavity 542, therebyproviding a relatively large fluid opening at lip seal 525. A largevolume of fluid can flow from input port 518 to output port 520.

[0082] When the plunger of actuator 142 or 143 seals control passages544A and 544B, pressure builds up in pilot chamber 542 due to the fluidflow from input port 518 through groove 538. The increased pressure inpilot chamber 542 together with the force of spring 540 displacelinearly, in a sliding motion over guide pin 536, fram member 526 towardsealing lip 529. When there is sufficient pressure in pilot chamber 542,diaphragm-like pliable member 528 seals input port chamber 519 at lipseal 525. Preferably, soft member 528 is designed to clean groove 538 ofguide pin 536 during the sliding motion.

[0083] The embodiment of FIG. 5 shows valve 500 having input chamber 519(and guide pin 536) symmetrically arranged with respect to passages544A, 544B and 546 (and the location of the plunger of actuator 142 or143). However, valve device 500 may have input chamber 519 (and guidepin 536) non-symmetrically arranged with respect to passages 544A, 544B(not shown) and passage 546. That is, this valve has input chamber 519(and guide pin 536) non-symmetrically arranged with respect to thelocation of the plunger of actuator 142 or 143. The symmetrical andnon-symmetrical embodiments are equivalent.

[0084] Referring to FIG. 5C, valve device 600 includes a valve body 613providing a cavity for a valve assembly 614, an input port 618, and anoutput port 620. Valve assembly 614 includes a proximal body 602, adistal body 604, and a fram member or assembly 626. Fram member 626includes a pliable member 628 and a support member 632. Pliable member628 may be a diaphragm-like member with a sliding seal 630. Supportmember 632 may be plunger-like member or a piston like member, buthaving a different structural and functional properties that aconventional plunger or piston. Valve body 602 provides a guide surface636 located on the inside wall that includes one or several grooves 638and 638A. These are novel grooves constructed to provide fluid passagesfrom input chamber located peripherally (unlike the central inputchamber shown in FIGS. 5 and 5B).

[0085] Fram member 626 defines a pilot chamber 642 arranged in fluidcommunication with actuator cavity 650 via control passages 644A and644B. Actuator cavity 650 is in fluid communication with output chamber621 via a control passage 646. Groove 638 (or grooves 638 and 638A)provides a communication passage between input chamber 619 and pilotchamber 642. Distal body 604 includes an annular lip seal 625co-operatively arranged with pliable member 628 to provide a sealbetween input port chamber 619 and output port chamber 621. Distal body624 also includes a flow channel 617 providing communication (in theopen state) between input chamber 619 and output chamber 621 for a largeamount of fluid flow. Pliable member 628 also includes sealing members629A and 629B (or one sided sealing member depending on the pressureconditions) arranged to provide a sliding seal with respect to valvebody 622, between pilot chamber 642 and input chamber 619. (Of course,groove 638 enables a controlled flow of fluid from input chamber 619 topilot chamber 642, as described above.)

[0086] The entire operation of valve device 600 is controlled by asingle actuator 142 or 143, which may include a solenoid, such as thebistable solenoid model no. AXB724 available from Arichell TechnologiesInc., West Newton, Mass. Alternatively, actuator 142 may include alatching actuator (as described in U.S. Pat. No. 6,293,516, which isincorporated by reference), a non-latching actuator (as described inU.S. Pat. No. 6,305,662, which is incorporated by reference), or anisolated operator 143 (as described in PCT Application PCT/US01/51098,which is incorporated by reference). In general, a number of solenoidvalves may be used such as described in U.S. Pat. No. 4,225,111. Analternative bistable solenoid is described in U.S. Pat. No. 5,883,557 or5,599,003.

[0087] Advantageously, valves 500 and 600 provide much higher flow ratesthan flow rates of prior art diaphragm valves. Furthermore, valves 500and 600 have a more predictable operation than standard piston valves.Curve 160 depicts a flow-rate (in gallons per minute) for a prior artdiaphragm valve for water pressures from about 6 psi to about 92 psi.Curve 162 depicts the flow-rate (in gallons per minute) through the“half size” valve of FIG. 1 for water pressures from about 6 psi toabout 92 psi. Curve 164 depicts a flow-rate (in gallons per minute)through the “two size” valve of FIG. 1 for water pressures from about 6psi to about 42 psi. In summary, the novel valve enables about three orfour times higher flow-rate than prior art diaphragm valves due to itslarger stroke of the fram member.

[0088]FIG. 6 illustrates another embodiment of an automatic faucetmounted to a countertop 12. The automatic faucet includes hot and coldwater lines 24 a and 24 b, respectively, connected to a mixing valve 25,which in turn is connected to an automatic valve device 501, shown indetail in FIGS. 6A and 6B. Automatic valve device 501 includes controlcircuitry (shown in FIG. 8 or 9) constructed and arranged to controlwater flow based on signals received from either a transceiver fordetecting presence of an object, or a proximity sensor. A suitableoptical transceiver is described in U.S. Pat. No. 5,979,500 or U.S. Pat.No. 5,984,262, both of which are incorporated by reference.

[0089] Automatic valve device 501 receives water input from a mixingvalve 25 and provides controlled water output to the faucet outlet 44.Automatic valve device 501 includes, valve body 502 coupled to an inputconnector 504, and an output connector 512. Valve body 502 includes avalve 500 (described in connection with FIGS. 5, 5A and 5B) and aremovable plug 503. The operation of automatic valve device 501 iscontrolled by actuator 142 or actuator 143 (described in detail inconnection with FIGS. 7 through 7F). Preferably, actuator 142 or 143 isscrewed to the body of valve 500. The entire geometry and design ofautomatic valve device 501 is arranged for easy access and servicing.Specifically, after removal of plug 503, the entire valve assemblyincluding actuator 142 or 143 can be pulled out of valve body 502 bypulling on a removal rod 568, as shown in FIG. 6B.

[0090] Referring still to FIGS. 6, 6A and 6B, automatic valve device 501includes a body 502 made of a durable plastic or metal. Preferably,valve body 502 is made of a plastic material but includes a metallicinput coupler 504 and a metallic output coupler 512. Input and outputcouplers 504 and 512 are made of metal, as known in the industry, sothat they can be used as gripping surfaces for a wrench used to connectthem to a water line leading to faucet output 44.

[0091] Due to its softer body, automatic valve device 501, includesinput and output couplers having a unique design that preventstightening the water line connection to any of the two valve couplersunless attaching the wrench on the surface of couplers 504 and 512.(That is, a plumber cannot tighten the waterlines by gripping on thevalve body 502.) Specifically, coupler 504 is rotatably attached to thevalve input port 506 using a sealing O-ring 507 and a C-clamp 505 thatfits into a groove 505 a. Similarly, output coupler 512 is rotatablyconnected to output port 508 of valve 502. This rotatable coupling isagain achieved by using an O-ring 509 and a C-clamp 510 that slides intoa slot 510 a. Therefore, due to the rotational movement, it is notpossible to tighten the input and output water lines by gripping ontoplastic body 502. This, in turn, protects the relatively soft plasticfrom being destroyed during installation.

[0092] Referring to FIG. 6B, a valve device 501 is assembled byinstalling an actuator 142 or 143 (with or without piloting button 705)onto valve body 522. Valve body 522 is tightened using threads 522 ainside body 560 also including the fram member with pliable member 528(shown in FIG. 6B). Automatic valve 501 also includes output port member570 with several orifices providing passages to output 520, similarly asdone by distal body 524 shown in FIG. 5A. After the individual valvepieces are tightened together the entire assembly is inserted insidevalve body 502 and dosed by distal plug 503, including O-ring 503 a,after water filter 552 is also inserted.

[0093] As described above, service rod 568 is designed to pull theentire valve assembly out of body 502, after removing of plug 503. Theremoval of the entire valve assembly also removes the attached actuator143 and piloting button 705. To enable easy installation and servicing,there are rotational electrical contacts located on a PCB at the distalend. Specifically, actuator 143 includes, on its distal end, two annularcontact regions that provide a contact surface for the correspondingpins, all of which can be gold plated for achieving high qualitycontacts. Alternatively, a stationary PCB can include the two annularcontact regions and the actuator may be connected to movable contactpins. Such distal, actuator contact assembly achieves easy rotationalcontacts by just sliding actuator 143 inside valve body 502.

[0094] Electronic faucets shown in FIGS. 2, 2A, and 6 may utilizevarious embodiments of isolated actuator 143, shown in FIGS. 7, 7B and7C. Isolated actuator 143 includes actuator body 701 comprising anactuator base 716, a ferromagnetic pole piece 725, a ferromagneticarmature 740 slideably mounted in an armature pocket formed inside abobbin 714. Ferromagnetic armature 740 includes a distal end 742 (i.e.,plunger 742) and an armature cavity 750 having a coil spring 748. Coilspring 748 includes reduced ends 748 a and 748 b for machine handling.Ferromagnetic armature 740 may include one or several grooves orpassages 752 providing communication from the distal end of armature 740(outside of actuator base 716) to armature cavity 750 and to theproximal end of armature 740, at the pole piece 725, for easy movementof fluid during the displacement of the armature.

[0095] Isolated actuator body 701 also includes a solenoid windings 728wound about solenoid bobbin 714 and magnet 723 located in a magnetrecess 720. Isolated actuator body 701 also includes a resilientlydeformable O-ring 712 that forms a seal between solenoid bobbin 714 andactuator base 716, and includes a resiliently deformable O-ring 730 thatforms a seal between solenoid bobbin 714 and pole piece 725, all ofwhich are held together by a solenoid housing 718. Solenoid housing 718(i.e., can 718) is crimped at actuator base 16 to hold magnet 723 andpole piece 725 against bobbin 714 and thereby secure windings 728 andactuator base 716 together.

[0096] Isolated actuator 143 also includes a resilient membrane 744 thatmay have various embodiments shown and described in connection withFIGS. 7D and 7E. As shown in FIG. 7, resilient membrane 764 is mountedbetween actuator base 716 and a piloting button 705 to enclose armaturefluid located a fluid-tight armature chamber in communication with anarmature port 752. Resilient membrane 764 includes a distal end 766,O-ring like portion 767 and a flexible portion 768. Distal end 766 comesin contact with the sealing surface in the region 708. Resilientmembrane 764 is exposed to the pressure of regulated fluid provided viaconduit 706 in piloting button 705 and may therefore be subject toconsiderable external force. Furthermore, resilient membrane 764 isconstructed to have a relatively low permeability and high durabilityfor thousands of openings and closings over many years of operation.

[0097] Referring to still to FIG. 7, isolated actuator 143 is provided,for storage and shipping purposes, with a cap 703 sealed with respect tothe distal part of actuator base 716 and with respect to piloting button705 using a resiliently deformable O-ring 732. Storage and shipping cap703 includes usually water that counter-balances fluid contained byresilient membrane 744; this significantly limits or eliminatesdiffusion of fluid through resilient membrane 744.

[0098] Isolated actuator 143 may be constructed either as a latchingactuator (shown in FIG. 7) or a non-latching actuator. The latchingembodiment includes magnet 723 (as shown) providing magnetic fieldhaving orientation and force sufficient to overcome the force of coilspring 748 and thereby retain armature 740 in the open state even afterthere is no drive current flowing in the solenoid's windings 728.

[0099] In the non-latching embodiment, there is no permanent magnet(i.e., no magnet 732). Thus, to keep armature 740 in the open state, adrive current must continue to flow in windings 728 to provide thenecessary magnetic field. Armature 740 moves to the closed state underthe force of spring 48 if there is no drive current. On the other hand,in the latching embodiment, a drive current is applied to windings 728in opposite directions to move armature 730 between the open and closedstates, but no drive current is necessary to maintain either state.

[0100] Referring still to FIG. 7, actuator base 716 includes a wide baseportion substantially located inside can 718 and a narrowed baseextension threaded on its outer surface to receive cap 703. The innersurface of the base extension threadedly engages complementary threadsprovided on the outer surface of piloting button 705. Membrane 764includes a thickened peripheral rim 767 located between the baseextension 32's lower face and piloting button 705. This creates afluid-tight seal so that the membrane protects the armature fromexposure to external fluid flowing in the main valve.

[0101] For example, the armature liquid may be water mixed with acorrosion inhibitor, e.g., a 20% mixture of polypropylene glycol andpotassium phosphate. Alternatively, the armature fluid may includesilicon-based fluid, polypropylene polyethylene glycol or another fluidhaving a large molecule. The armature liquid may in general be anysubstantially non-compressible liquid having low viscosity andpreferably non-corrosive properties with respect to the armature.Alternatively, the armature liquid may be Fomblin or other liquid havinglow vapor pressure (but preferably high molecular size to preventdiffusion).

[0102] If there is anticorrosive protection, the armature material canbe a low-carbon steel, iron or any soft magnetic material; corrosionresistance is not as big a factor as it would otherwise be. Otherembodiments may employ armature materials such as the 420 or 430 seriesstainless steels. It is only necessary that the armature consistessentially of a ferromagnetic material, i.e., a material that thesolenoid and magnet can attract. Even so, it may include parts, such as,say, a flexible or other tip, that is not ferromagnetic.

[0103] Resilient membrane 764 encloses armature fluid. located afluid-tight armature chamber in communication with an armature port 752or 790 formed by the armature body. Furthermore, resilient membrane 764is exposed to the pressure of regulated fluid in main valve and maytherefore be subject to considerable external force. However, armature740 and spring 750 do not have to overcome this force, because theconduit's pressure is transmitted through membrane 764 to theincompressible armature fluid within the armature chamber. The forcethat results from the pressure within the chamber thereforeapproximately balances the force that the conduit pressure exerts.

[0104] Referring still to FIGS. 7, 7A, 7B and 7C, armature 740 is freeto move with respect to fluid pressures within the chamber between theretracted and extended positions. Armature port 752 or 790 enables theforce-balancing fluid displaced from the armature chamber's lower wellthrough the spring cavity 750 to the part of the armature chamber fromwhich the armature's upper end (i.e. distal end) has been withdrawn uponactuation. Although armature fluid can also flow around the armature'ssides, arrangements in which rapid armature motion is required shouldhave a relatively low-flow-resistance path such as the one that port 752or 790 helps form. Similar considerations favor use of anarmature-chamber liquid that has relatively low viscosity. Therefore,the isolated operator (i.e., actuator 143) requires for operation onlylow amounts of electrical energy and is thus uniquely suitable forbattery operation.

[0105] In the latching embodiment shown in FIG. 7, armature 740 is heldin the retracted position by magnet 723 in the absence of a solenoidcurrent. To drive the armature to the extended position thereforerequires armature current of such a direction and magnitude that theresultant magnetic force counteracts that of the magnet by enough toallow the spring force to prevail. When it does so, the spring forcemoves armature 740 to its extended position, in which it causes themembrane's exterior surface to seal against the valve seat (e.g., theseat of piloting button 705). In this position, the armature is spacedenough from the magnet that the spring force can keep the armatureextended without the solenoid's help.

[0106] To return the armature to the illustrated, retracted position andthereby permit fluid flow, current is driven through the solenoid in thedirection that causes the resultant magnetic field to reinforce that ofthe magnet. As was. explained above, the force that the magnet 723exerts on the armature in the retracted position is great enough to keepit there against the spring force. However, in the non-latchingembodiment that doesn't include magnet 723, armature 740 remain in theretracted position only so long as the solenoid conducts enough currentfor the resultant magnetic force to exceed the spring force of spring748.

[0107] Advantageously, diaphragm membrane 764 protects armature 740 andcreates a cavity that is filled with a sufficiently non-corrosiveliquid, which in turn enables actuator designers to make more favorablechoices between materials with high corrosion resistance and highmagnetic permeability. Furthermore, membrane 764 provides a barrier tometal ions and other debris that would tend to migrate into the cavity.

[0108] Diaphragm membrane 764 includes a sealing surface 766, which isrelated to the seat opening area, both of which can be increased ordecreased. The sealing surface 766 and the seat surface of pilotingbutton 705 can be optimized for a pressure range at which the valveactuator is designed to operate. Reducing the sealing surface 766 (andthe corresponding tip of armature 740) reduces the plunger area involvedin squeezing the membrane, and this in turn reduces the spring forcerequired for a given upstream fluid-conduit pressure. On the other hand,making the plunger tip area too small tends to damage diaphragm membrane764 during valve closing over time. Preferable range of tip-contact areato seat-opening area is between 1.4 and 12.3. The present actuator issuitable for variety of pressures of the controlled fluid. includingpressures about 150 psi. Without any substantial modification, the valveactuator may be used in the range of about 30 psi to 80 psi, or evenwater pressures of about 125 psi.

[0109] Referring still to FIGS. 7, 7A, 7B and 7C, piloting button 705has an important novel function for achieving consistent long-termpiloting of the diaphragm valve shown in FIG. 4, or the fram valve shownin FIG. 4A. Solenoid actuator 142 or 143 together with piloting button705 are installed together as one assembly into the electronic faucet;this minimizes the pilot-valve-stroke variability at the pilot seat inregion 708 (FIGS. 7, 7B and 7C) with respect to the closing surface(shown in detail in FIG. 7E), which variability would otherwise afflictthe piloting operation. This installation is faster and simpler thanprior art installations.

[0110] The assembly of operator 701 and piloting button 705 is usuallyput together in a factory and is permanently connected thereby holdingdiaphragm membrane 764 and the pressure loaded armature fluid (atpressures comparable to the pressure of the controlled fluid). Pilotingbutton 705 is coupled to the narrow end of actuator base 716 usingcomplementary threads or a sliding mechanism, both of which assurereproducible fixed distance between distal end 766 of diaphragm 764 andthe sealing surface of piloting button 705. The coupling of operator 701and piloting button 705 can be made permanent (or rigid) using glue, aset screw or pin. Alternatively, one member may include an extendingregion that is used to crimp the two members together after screwing orsliding on piloting button 705.

[0111] It is possible to install solenoid actuator 142 or 143 withoutpiloting button 705, but this process is somewhat more cumbersome.Without piloting button 705, the installation process requires firstpositioning the pilot-valve body (102 d in FIG. 4, or 514 in FIGS. 4Aand 5) with respect to the main valve and then securing to the actuatorassembly onto the main valve as to hold the pilot-valve body in place.If proper care is not taken, there is some variability in the positionof the pilot body due to various piece-part tolerances and possibledeformation. This variability creates variability in the pilot-valvemember's stroke. In a low-power pilot valve, even relatively smallvariations can affect timing or possibly sealing force adversely andeven prevent the pilot valve from opening or closing at all. Thus, it isimportant to reduce this variability during installation, fieldmaintenance, or replacement. On the other hand, when assembling solenoidactuator 142 or 143 with piloting button 705, this variability iseliminated or substantially reduced during the manufacturing process,and thus there is no need to take particular care during fieldmaintenance or replacement.

[0112] Referring to FIG. 7, thus piloting button 705 enables a novel wayof assembling a pilot-valve-operated automatic flow controller, used inthe faucet embodiments of FIGS. 2 and 2A, that achieves a consistentlong-term performance. The novel method of assembling apilot-valve-operated automatic flow controller includes providing a mainvalve assembly (e.g., valve assembly 96 shown in FIG. 4 without usingactuator 142; or a valve assembly 96 s shown in FIG. 4A without usingactuator 143) and a pilot-valve assembly 143 (FIG. 7) includingstationary actuator 701 and piloting button 703 (i.e., pilot bodymember) that includes pilot-valve inlet 706, a pilot-valve seat locatedat 708, and a pilot-valve outlet 710. The assembly method includessecuring the pilot-valve assembly to the main valve assembly in a waythat fluid flowing from the pressure-relief outlet (e.g., passage 136 ain FIG. 4 or passages 544 a and 544 b in FIG. 5) of the main valve mustflow through pilot-valve inlet 706, past the pilot-valve seat, andthrough pilot-valve outlet 710, whereby the pilot-valve assembly ispositioned to control relief of fluid pressure in the pressure chamber(i.e., pilot chamber 132 in FIG. 4, or pilot chamber 542 in FIG. 4A) ofthe main valve assembly.

[0113] As described above, the main valve assembly includes a main valvebody with a main-valve inlet, a main-valve seat, a main-valve outlet, apressure chamber (i.e., a pilot chamber), and a pressure-relief outletthrough which the pressure in the pressure chamber (pilot chamber) canbe relieved, wherein the main valve member can be diaphragm 126 (FIG.4), a piston, or a fram member 526 (FIG. 5A), all of which are movablebetween a closed position, in which the main valve member seals againstthe main-valve seat (i.e.i circular seat 124 in FIG. 4, or circular seat525 in FIG. 5) thereby preventing flow from the main inlet (e.g., inputport 518 in FIG. 5) to the main outlet (e.g., output port 520 in FIG.5).

[0114] Referring to FIGS. 7D and 7E, as described above, diaphragmmembrane 764 includes an outer ring 767, flex region 768 and tip or seatregion 766. The distal tip of the plunger is enclosed inside a pocketflange behind the sealing region 766. Preferably, diaphragm membrane 764is made of EPDM due to its low durometer and compression set by NSF part61 and relatively low diffusion rates. The low diffusion rate isimportant to prevent the encapsulated armature fluid from leaking outduring transportation or installation process. Alternatively, diaphragmmember 764 can be made out of a flouro-elastomer, e.g., VITON, or asoft, low compression rubber, such as CRI-LINE® flouro-elastomer made byCRI-TECH SP-508. Alternatively, diaphragm member 764 can be made out ofa Teflon-type. elastomer, or just includes a Teflon coating.Alternatively, diaphragm member 764 can be made out NBR (natural rubber)having a hardness of 40-50 durometer as a means of reducing theinfluence of molding process variation yielding flow marks that can formmicro leaks of the contained fluid into the surrounding environment.Alternatively, diaphragm member 764 includes a metallic coating thatslows the diffusion thru the diaphragm member when the other is dry andexposed to air during storage or shipping of the assembled actuator.

[0115] Preferably, diaphragm member 764 has high elasticity and lowcompression (which is relatively difficult to achieve). Diaphragm member764 may have some parts made of a low durometer material (i.e., parts767 and 768) and other parts of high durometer material (front surface766). The low compression of diaphragm member 764 is important tominimize changes in the armature stroke over a long period of operation.Thus, contact part 766 is made of high durometer material. The highelasticity is needed for easy flexing diaphragm member 764 in regions768. Furthermore, diaphragm part 768 is relatively thin so that thediaphragm can deflect, and the plunger can move with very little force.This is important for long-term battery operation.

[0116] Referring to FIG. 7E, another embodiment of diaphragm membrane764 can be made to include a forward slug cavity 772 (in addition to therear plunger cavity shaped to accommodate the plunger tip). The forwardslug cavity 772 is filled with a plastic or metal slug 774. The forwardsurface 770 including the surface of slug 774 is cooperatively arrangedwith the sealing surface of piloting button 705. Specifically, thesealing surface of piloting button 705 may include a pilot seat 709 madeof a different material with properties designed with respect to slug774. For example, high durometer pilot seat 709 can be made of a highdurometer material. Therefore, during the sealing action, resilient andrelatively hard slug 772 comes in contact with a relatively soft pilotseat 709. This novel arrangement of diaphragm membrane 764 and pilotingbutton 705 provides for a long term, highly reproducible sealing action.

[0117] Diaphragm member 764 can be made by a two stage molding processwhere by the outer portion is molded of a softer material and the innerportion that is in contact with the pilot seat is molded of a harderelastomer or thermo-plastic material using an over molding process. Theforward facing insert 774 can be made of a hard injection moldedplastic, such as acceptable co-polymer or a formed metal disc of anon-corrosive non-magnetic material such as 300 series stainless steel.In this arrangement, pilot seat 709 is further modified such that itcontains geometry to retain pilot seat geometry made of a relativelyhigh durometer elastomer such as EPDM 0 durometer. By employing thisdesign that transfers the sealing surface compliant member onto thevalve seat of piloting button 705 (rather than diaphragm member 764),several key benefits are derived. Specifically, diaphragm member 764 avery compliant material. There are substantial improvements in theprocess related concerns of maintaining proper pilot seat geometryhaving no flow marks (that is a common phenomena requiring carefulprocess controls and continual quality control vigilance). This designenables the use of an elastomeric member with a hardness that isoptimized for the application.

[0118]FIG. 7F is a cross-sectional view of another embodiment of anarmature bobbin used in the actuator shown in FIGS. 7 through 7C. Thebobbin's body is constructed to have low permeability to the armaturefluid. For example, bobbin 714 includes metallic regions 713, which arein contact with the armature fluid, and plastic regions 713 a, which arenot in contact with the armature fluid.

[0119] According to another embodiment, the electronically controlledfaucet is constructed and arranged to prevent bacterial or othercontamination, especially bacterial growth in water remaining inside thefaucet. The “antibacterial” faucet is mainly suitable for medicalfacilities such as operating rooms or emergency rooms. The“anti-bacterial” faucet includes mainly non-metallic conduits and valveelements in contact with water to substantially reduce or eliminatebacterial growth on their surfaces, and even act as inhibitors ofbacterial growth. The “anti-bacterial” faucet also executes periodicallya novel flushing algorithms.

[0120] Specifically, in the “antibacterial” faucet, metal conduits aremade to have smooth bores (i.e., without surface crevices), or arereplaced by plastic conduits. Suitable conduits and faucet elements aremade of acetal co-polymers that are known to be bacterial growthinhibitors (and some of them currently used in human implantapplications). The above-described valve elements are made of similarmaterials including elastomeric members made of EPDM that has proven asan inhospitable media for micro organism growth. In addition tobio-compatible-materials, the material surfaces may be coated orimbedded with suitable chemical agents for preventing or inhibitingbacterial or other growth.

[0121] In addition to bio-compatible materials, the “anti-bacterial”faucet executes various novel flushing algorithms that remove stagnatewater residing inside the faucet. The flushing algorithms are designedto flush any potential bacterial growth, depending on the watertemperature. The “anti-bacterial” faucet may include a temperaturesensor providing temperature data to control circuitry, and thuscorrelating potential bacterial growth with the measured watertemperature. Furthermore, the use of isolated actuator 143 reduces theamount of stagnate water located inside the control valves.Specifically, diaphragm membrane 764 prevents delivery of armature fluidfrom armature cavity to the faucet output port, while the pilotingchamber (including region 708) is periodically flushed.

[0122] At predetermined flushing intervals, the control circuitryexecutes a flushing algorithm removing water from inside of the faucetincluding control valves.

[0123] The purging algorithm automatically turns on the water for a fewseconds when a user is not present to remove standing water whichresides in the faucet including the faucet's inlet and outlet conduitthat is also exposed to air born pathogens. The periodicity of the purgecycle can be matched to the average growth of bacteria in tempered waterwith further the ability to alter the periodicity if the watertemperature is higher (which increases growth rate). The periodicitycontrol is achieved by means of user settable timings and/or the use ofa temperature measurement element that is integrated into the controlcircuitry and in turn is used to determine automatically the neededpurge rate.

[0124] Referring to FIG. 8, a circuit/block diagram shows the majorelectrical components located on printed circuit board 206 which controlthe operation of faucet 10. A microcontroller 332 operates a driver 334which powers the solenoid 142 of the valve assembly 96. In some faucetembodiments, the microcontroller 332 may also receive an input from anobject sensor 336 which is part of a proximity transceiver 338 mountedto the faucet spout cover plate 326 just above opening 46 therein asshown in phantom in FIG. 1. Transceiver 338 may be of a known infraredtype commonly found on automatic faucets and consisting of a lightemitting diode which directs a beam of infrared light downward from thespout, and an infrared sensor which detects light reflected from a handor other object positioned under the faucet spout.

[0125] The circuit diagram also includes a D-type flip-flop 342 whose Dinput receives pulses from microcontroller 332 by way of a resistor 344.That D input of the flip-flop is also connected via a capacitor 346 tothe metal pad 218 comprising touch sensor 42. The Q output of a D-typeflip-flop is the value that it's D input had at the time of the lastleading edge of a pulse train applied to the flip-flops' CLOCK (CLK)input terminal.

[0126] Normally, when a user has placed his hand or finger in thevicinity of the touch sensor 42, the Q output of flip-flop 342 remainsasserted continuously. The microcontroller 332 produces arectangular-wave clock signal which is applied via resistor 344 to the Dinput terminal of flip-flop 342. That same signal is applied to aresistor 348 and an inverter 352 to the CLK input terminal of flip-flop342. However there is a delay in the transmission of that pulse frommicrocontroller 332 to the CLK input terminal of flip-flop 342 becauseof the presence of a plurality of capacitors 354 a to 354 e whichcapacitively load the input circuit of converter 352 as will bedescribed in more detail below. The value at the D input port offlip-flop 342 therefore stabilizes at the higher level before the risingleading edge of the clock pulses from inverter 352 reach the flip-flop'sCLK input terminal. Therefore, the Q output of the flip-flop is high.However this situation changes when a user's hand is very dose to thetouch sensor 42 or actually touches it. This hand contact or proximityhas the effect of capacitively loading the D input-terminal of flip-flop342; it may typically result in a capacitance on the order of 300 pFbetween sensor 42 and ground.

[0127] The inverter input is also connected via a diode 356 and aresistor 358 to the D input terminal of flip-flop 342. This imposes adelay at the D input 342 of flip flop affecting the pulse level to theextent that the edge of the clock signal applied to the clock input ofthe flip-flop now occurs before the D input has reached the high level.Therefore, the flip-flip's Q output remains low. The microcontrollerreceives the compliment of that Q output at its input 362 and therebyinfers that a user has touched the sensor 42.

[0128] However, various environmental factors can also load the touchsensor 42. Therefore, in a preferred embodiment of the invention, themicrocontroller 332 so adjusts the circuit's sensitivity as to minimizethe likelihood of erroneous human-contact indications. As does this byemploying lines 364 a to 364 d to ground selected one of the capacitors354 a to 354 d, while allowing the others to float. By selectivelygrounding these capacitors, the microcontroller can choose among 16different sensitivity levels. This sensitivity adjustment is donedynamically to account for changing environmental conditions or a user'snervousness or hesitancy for being considered as-multiple inputs to thefaucet's touch sensing circuitry. The microcontroller 332 monitors theoutput of flip-flop 342 and changes the sensitivity level of the sensingcircuit according to an adapting or dynamic sensing algorithm to bediscussed in connection with FIG. 8A.

[0129] The microcontroller 332 operates, as many battery-operated do, ina sleep/wake sequence. Most of the time, the controller is “asleep”: itreceives only enough power to maintain the state of certain volatileregisters, but it is not being clocked or executing instructions. Thissleep state is interrupted periodically, say, every 120 ms, with a“wake” state, in which it executes various subroutines before returningto its sleep state. The duration of the wake state is typically a verysmall fraction of the controller's sleep state duration.

[0130] One of the routines performed by microcontroller 332 when itawakens is the sensitivity adjustment routine depicted in the FIG. 8Aflow chart. In FIG. 8A, block 400 represents the start of that routineand block 402 represents sampling the value of the signal applied to themicrocontroller sense input 362 shown in FIG. 8. If because of theoperation just described, that input's level indicates that a user istouching the touch sensor 42, the controller sets to zero a non-touchtimer representing how long it has been since the faucet detected aperson's touch at touch sensor 42. Blocks 404 and 406 represent thissubroutine. As will be explained presently, the non-touch timer is usedto determine when to make a sensitivity adjustment.

[0131] Although a touch detection is usually the basis for causing thefaucet valve to open, the system is sometimes in a mode in which it isused instead to determine when to adjust sensitivity. Block 408represents reading a flag to determine whether a sensitivity adjustmentor a touch cycle is currently in progress. If it is not, the routineproceeds to increment a touch timer if that timer has not alreadyreached a maximum value. Blocks 410 and 412 represent that incrementingoperation.

[0132] The touch timer indicates how long a touch detection has beenreported more or less continuously. An excessive touch duration willcause the system to infer that the touch detection resulted fromsomething other than a human user and that the system's sensitivityshould therefore be reduced to avoid such erroneous detections. Beforethe system test that duration for that purpose, however, it firstperforms a de-bounce operation, represented by blocks 414 and 416, inwhich it determines whether the number of successive touch detectionsexceeds three. If it has, then at block 418, the system resets the touchcount to zero and sets a flag that will tell other routines, notdiscussed here, to open the valve. If these three detections have notoccurred in a row, on the other hand, the system does not yet considerthe touch valid and that flag is not set.

[0133] The system then performs a test, represented by block 420 todetermine whether it should reduce the system's sensitivity. If thetouch timer represents a duration less than 15 seconds, the routinesimply ends at block 421. Otherwise, it resets the flag that wouldotherwise cause other routines to open the valve. It also sets a flag toindicate that the system is in its sensitivity or adjustment mode andcauses a decrease in sensitivity by one step. That is, it so changes thecombination of capacitors 354 a to 354 e in the circuit of FIG. 8 thatare connected to ground that the signal applied to the CLK input offlip-flop 342 is increased. Resultantly, a greater loading of the touchsensor 42 will be required for the flip-flop 342 to indicate that atouch has occurred. Block 422 represents taking those actions.

[0134] It may occur in some situations that the sensitivity was alreadyas low as it could go. If that happens, the system is in an errorcondition, and subsequent circuitry should take appropriate action. Thisis determined at block 424. If it has, then the routine sets an errorflag as indicated at block 426 and the routine ends at block 421. If thesystem is not in that error condition, the routine performs the steps atblocks 406 and 408 as before. This time, however, thesensitivity-adjustment flag is set so that the test at block 408 resultsin the routines jumping to The step at block 422 to repeat thesensitivity-reduction sequence just described.

[0135] Referring to the right hand side of FIG. 8A, if the block 404step yields an indication that no touch has been detected by the touchsensor 42, the routine resets the touch counter to zero as indicated atblock 432.

[0136] As was described previously, an extended period of touchdetection will cause the system to reduce its sensitivity, on the theorythat detection for so long a period could not have been the result of alegitimate human contact. If contact absence has been indicated for anextended period, on the other hand, it is logical to conclude that thecurrent capacitive loading provided by capacitors 354 a to 354 e (FIG.8) is consistent with contact absence but that any greater capacitanceis likely to be an indication of legitimate contact of the touch sensor42. The system therefore responds to an extended period of detectionabsence by increasing the sensitivity to a value just below one thatwould cause touch detection with the currently prevailing capacitanceloading by capacitors 354 a to 354 e (FIG. 8).

[0137] To this end, the routine in FIG. 8A increments the non-touchtimer if that timer has not exceeded a selective maximum value, e.g. 6seconds. Blocks 434 and 436 represent that operation. Since this pointin the routine is reached as a result of the indication of block 404that no touch has been detected, it would seem logical to reset thetouch timer to zero. However, to make the illustrated system more robustto noise that could cause a non-contact indication to occur momentarilyin the midst of an extending contact, the illustrated arrangementinstead merely decrements the touch timer towards zero if it has not yetreached that value. Blocks 438 and 440 represent the decrementing ofthat timer.

[0138] Now if such touch-timer decrementing has occurred enough timesfor that timer's value to have been reduced by a selected value, say,two seconds, the system can rule out the possibility that the lack oftouch detection was simply caused by noise. Therefore, since the systemhas assumed the sensitivity-adjustment mode as a result of that timerhaving reached 15 seconds, its count having been decremented to 13seconds, can be considered as an indication that contact with the touchsensor 42 has actually ended. The touch timer is therefore set to zeroand the system leaves the sensitivity-adjustment mode as indicated byblocks 442, 444 and 446.

[0139] At block 448, the routine then tests the non-touch timer todetermine whether the absence of touch detection has lasted long enoughto justify trying a sensitivity increase. If not, the routine ends atblock 421. Otherwise, the routine makes a back-up-copy of the currentsensitivity at block 450 and then proceeds to determine whether anincrease in sensitivity will cause a touch detection. Of course, thesensitivity cannot be increased if it is already at its maximum value soat block 452, the routine goes to END block 421. However if thesensitivity is not yet at its maximum value, it is increased by one stepas indicated at block 458. This is part of the sensitivity-adjustment sothat that step includes setting the sensitivity-adjustment mode flag.The microcontroller 332 (FIG. 8) then samples the output of flip-flop342 again, as indicated at block 454 and, as block 456 indicatesbranches on the result. In particular, if a sensitivity increase has notresulted in an apparent touch detection, then the sensitivity isincreased again (because it has not reached a maximum), and the outputof flip-flop 342 is sensed again.

[0140] This continues until an apparent touch is detected. Since thesensitivity adjustment scheme is based on the assumption that therereally is no valid contact at touch sensor 42, the sensitivity is thusreduced back by one step so that it is at the highest level that yieldsno touch indication. Block 458 represents this operation.

[0141] Now that a sensitivity-adjustment has been made, the non-touchtimer is reset to zero as indicate at block 460 so that the sensitivitywill not be reset again on the next controller wake cycle. The routinethen ends at block 421.

[0142]FIG. 9 is a block diagram of another embodiment of controlcircuitry 800 used for operating electronic faucets shown in FIGS. 1 and6. Control circuitry 800 includes a microcontroller 802 designed tocommunicate with an IR emitter 804 and an IR receiver 806, formingoptical transceiver 338 used in the faucets. Microcontroller 802 alsoreceives “wake-up” signals from a timer (i.e., watchdog) 802, forexample, every 250 msec. The entire circuitry is powered by a batterypower source 812, and also includes a battery detector 813. Afterreceiving appropriate control signals from optical transceiver 338,microcontroller 802 sends an actuation signal to a solenoid driver 810,which in turn provides a coil drive signal (latch or unlatch current) tothe coil 728 of operator 142 or 143. Then microcontroller 802 goes to a“sleep” mode.

[0143] Microcontroller 802 is programmed to operate the entire circuit800 while conserving battery power using a sleep mode. Microcontroller802 receives a reset signal from a timer 808 every, for example, 250msec, and then wakes up and performs a detection cycle. Timer 808 may beRC circuit based or crystal oscillator based, which may be internal tothe microcontroller Microcontroller 802 provides current to IR emitter804 that emits an IR beam and receives signal from IR detector 806, asknown in the art. The operation of the optical transceiver 338 isdescribed in U.S. Pat. No. 5,979,500 or U.S. Pat. No. 5,984,262, and isalso described in co-pending U.S. application Ser. Nos. 10/012,252 and10/012,226, all of which are incorporated by reference. Microcontroller802 may be microcontroller COP8SAB and COP8SAC made by NationalSemiconductor, or microcontroller TMP86c807M made by Toshiba. To savepower and significantly extend battery operation, the wake-up period ismuch shorted than the sleep period. Depending on the controllers mode,the sleep time may be 100 msec, 300 msec, or 1 sec.

[0144] Microcontroller 802 provides current to IR emitter 804 that emitsan IR beam and receives signal from IR detector 806, both of which areset initially the detection distance of 7.5 inches. That is, initiallythe sensitivity of object detection (e.g., user's hands) is set for 7.5inches, but this can be altered in an autocalibration cycleautomatically performed by microcontroller 802.

[0145] The electronic faucet can communicate with a user by a novel“burst interface” that provides signals to a user in form of waterbursts emitted from the faucet. Alternatively, the electronic faucet mayinclude novel an optical or acoustic interface. The electronic faucet isdesigned to prevent wasting of water when for example an objectpermanently located in a sink.

[0146] Microcontroller 802 is programmed to automatically go to variousmodes depending on the state of optical transceiver 338, batterydetector 814, or any other element. For example, microcontroller 802 isdesigned to go automatically into a self-calibration mode afterdetecting an object for a preset duration (for example, 15 or 20seconds). If transceiver 338 senses an object located in a sink at adistance of 7.5 inches for 15 seconds, microcontroller 802 directsemission of two water pulses (to signal to a user) and starts a selfcalibration routine that determines a new detection distance. In thisroutine, transceiver 338 detects the distance to the “permanently”located object and set up a new background values for IR emitter or IRdetector. Then, microcontroller 802 directs driver 810 to emit threeshort bursts of water to signal the end of the self calibration mode.After executing the self calibration, the “permanently” located objectis “seen” as background and thus doesn't trigger valve opening.

[0147] A user can initiate the self calibration mode by placing anobject in front of, transceiver 338, and then after two bursts at aselected distance that the system will determine as a new backgrounddistance. A user can initiate also other modes, by for example coveringoptical transceiver 338.

What is claimed is:
 1. a faucet including a sensor-based flow-controlsystem, comprising: a conduit having at least one fluid inlet and anoutlet for providing fluid; a main valve interposed in said conduit andcontrolled by an electromechanical actuator receiving control signalsfor switching between an open state of said valve permitting fluid flowthrough the conduit, and a closed state of said valve preventing fluidflow through the conduit; and a sensor for generating sensor outputsignals to an electronic control circuit constructed and arranged toprovide said control signals to said electromechanical actuator.
 2. Thecontrol system of claim 1 wherein the control circuit begins a timinginterval only if no previous timing interval is incomplete.
 3. Thecontrol system of claim 1 wherein the object sensor includes an infraredobject detector.
 4. The control system of claim 3 wherein the infraredobject detector is an active infrared object detector.
 5. The controlsystem of claim 4 wherein the infrared object detector is a passiveinfrared object detector.
 6. The control system of claim 1 wherein theobject sensor includes an ultrasonic object detector. 7-20. cancelled21. An electronic faucet comprising a housing; at least one fluid inletline extending into the housing; a fluid outlet from the housing; asolenoid valve in the housing controlling the fluid flow between said atleast one inlet line in the outlet, and a control circuit forcontrolling the opening and closing of the valve.
 22. A valve device,comprising: a fluid input port and a fluid output port; a valve bodydefining a valve cavity and including a valve closure surface; and afram assembly providing two pressure zones and being movable within saidvalve cavity with respect a guiding member; said fram assembly beingconstructed to move to an open position enabling fluid flow from saidfluid input port to said fluid output port upon reduction of pressure ina first of said pressure zones; and being constructed to move to aclosed position, upon increase of pressure in said first pressure zone,creating a seal at said valve closure surface.
 23. The valve device ofclaim 22, wherein said two pressure zones include two chambers separatedby said fram assembly and wherein said first pressure zone includes apilot chamber.
 24. The valve device of claim 23 including an operatorconstructed and arranged to release pressure in said pilot chamber andthereby initiate movement of said fram member from said closed positionto said open position.
 25. The valve device of claim 24, wherein saidoperator includes a latching actuator.
 26. The valve device of claim 24,wherein said operator includes a non-latching actuator.
 27. The valvedevice of claim 24, wherein said operator includes an actuator having anisolation membrane for containing fluid inside a plunger cavity of saidactuator.
 28. The valve device of claim 22 wherein said fram assemblyincludes a pliable member and a stiff member, said pliable member beingconstructed to come in contact with said valve closure surface to formsaid seal in said closed position.
 29. The valve device of claim 28,wherein said valve closure surface includes a lip providing said seal insaid closed position.
 30. The valve device of claim 22 including a biasmember.
 31. The valve device of claim 30 wherein said bias member isconstructed and arranged to assist movement of said fram member fromsaid open position to said closed position.
 32. The valve device ofclaim 30 wherein said bias member includes a spring.
 33. The valvedevice of claim 30 wherein said guiding member includes a pin.
 34. Thevalve device of claim 33 wherein said pin includes a grove.
 35. Thevalve device of claim 22 wherein, wherein said two pressure zonesinclude two chambers separated by said fram assembly and wherein saidfirst pressure zone includes a pilot chamber and a second of saidpressure zones includes an input chamber; and wherein said guidingmember includes a pin having a grove providing a passage from said inputchamber to said pilot chamber.
 36. The valve device of claim 23including a manual operator constructed and arranged to release pressurein said pilot chamber and thereby initiate movement of said fram memberfrom said closed position to said open position.
 37. The valve device ofclaim 23 including an electromagnetic operator constructed and arrangedto displace a magnetic element and thereby release pressure in saidpilot chamber to initiate movement of said fram member from said closedposition to said open position.
 38. A method of controlling fluid flow,comprising: providing a fluid input port and a fluid output portassociated with a valve body defining a valve cavity and including avalve closure surface; providing a fram assembly defining two pressurezones and being movable within said valve cavity with respect a guidingmember; reducing a pressure in a first of said pressure zones andthereby initiating movement of said fram assembly to an open positionenabling fluid flow from said fluid input port to said fluid outputport; and closing a control passage to increase of pressure in saidfirst pressure zone and thereby initiating movement of said framassembly from said open position to said closed position preventingfluid flow from said fluid input port to said fluid output port. 39-45.cancelled
 46. A method for controlling the sensor-based flow-controlsystem comprising: providing a conduit having at least one fluid inletand an outlet for providing fluid, a main valve interposed in saidconduit and controlled by an electromechanical actuator receivingcontrol signals for switching between an open state of said valvepermitting fluid flow through the conduit, and a closed state of saidvalve preventing fluid flow through the conduit; and a sensor forgenerating sensor output signals to an electronic control circuitconstructed and arranged to provide said control signals to saidelectromechanical actuator; sensing a user located near said sensor; andcommunicating to said user a state of said flow control system byselectively switching between said open state and said closed state.